UPDATED: Pensioner dies in motorway crash
The motorway was closed for around two and a half hours to allow investigation work to take place.
The man, who was in a Volvo, was pronounced dead at the scene while a woman in her seventies was airlifted to the John Radcliffe hospital in Oxford with serious injuries.
Anyone with information about the incident is asked to contact investigating officer PC Julia Stroud quoting URN 859 (2/3) via the police enquiry centre on 101.
Alternatively, contact Crimestoppers anonymously on 0800 555 111,